home theater

13 Articles

The Samsung PS-WTX500 subwoofer is designed to be used as part of a 5.1 channel home theater system, but not just any system. It contains the amplifiers for all the channels, but they’ll only function when the subwoofer is connected to the matching receiver. [Alejandro Zarate] figured there must be some way to unlock the system’s full functionality without being limited to the original receiver, he just needed to reverse engineer how the subwoofer worked.

All the wires tuck underneath the Arduino

The result is a fantastically well documented write-up that covers the whole process, starting with how [Alejandro] identified and researched the Pulsus PS9829B Digital Audio Processor (DAP). Documentation for this particular chip seems hard to come by, but he was able to find a similar chip from the same manufacturer that was close enough to put him on the right track. From there, he started studying the SPI communications between the DAP and the subwoofer’s S3P70F4 microcontroller.

After analyzing the communication between the two chips, [Alejandro] pulled the S3P70F4 off the board and wired an Arduino Pro Mini 328 in its place. The Arduino was quite a bit larger than the original microcontroller, but with some careful wiring, he manged a very professional looking installation. Short of coming up with a custom PCB adapter, we don’t think it could look much better.

With some relatively straightforward code and a listing of the captured byte sequences, the Arduino was able to power up the PS-WTX500’s amplifiers and handle the incoming audio signal as a stand-alone device.

There was a time when you could hold onto a TV or A/V receiver for the better part of the decade and not feel as though you were missing out on the latest and greatest features. But today you’re lucky to get three years out of a “smart” TV before it’s either supplanted by a vastly improved version, or falls victim to some weird issue that (surprise, surprise) means you need to buy a new one.

A simple touch interface hosted on the ESP8266

Not content with the status quo of planned obsolescence, [aamarioneta] recently set out to add a sprinkling of modern convenience to a circa 2008 Denon AVR 2308 home theater receiver. Like any good A/V receiver, the AVR 2308 features a dizzying array of ports on the back panel, one of which happens to be for an external infrared receiver. This turned out to be the perfect place to jack in an ESP8266, earning this 12 year old receiver an honorary membership into the Internet of Things.

The interesting thing about this hack is that there’s actually no IR involved. Sure, the code could be used to drive an IR LED attached to the ESP8266’s GPIO pins, and the AVR 2308 would respond as if the original remote was being used; but where’s the fun in that? Thanks to the receiver port, they’re able to inject the IR codes directly into the device. It’s the same protocol, just without the photons.

With a simple web-interface running on the ESP8266, they can control the AVR 2308 from a smartphone’s browser anywhere in the house. From here it would only take a few more lines of code to tie it into an existing home automation system or add in support for Alexa voice control.

Ever since purchasing this house, [Ed] Always wanted a to turn his living room into a home theater, but not just any old projector and a white wall would do. He wanted the whole experience. [Ed] Started with a slightly damaged 12′ wide 4:3 roll up projector screen, he removed the damaged bottom portion and built a static frame to support the now 16:9 screen. Before he could mount the screen, he needed to drywall over a window that was inconveniently located. With the screen now in place, [Ed] framed out the elevated seating platform and steps with some 2×12 topped off with plywood. Next, the carpet that was sitting directly below the platform and steps was removed and then secured on top. Down firing LED fixtures were installed in the steps, to give them that movie theater look and feel. To provide the image, a refurbished HD projector acquired from the Bay of Electronics, was installed in the loft above the living room.

With the theater functional, [Ed] turned his attention to theater decorations. Dimmable ambiance lighting fixtures, using laser cut acrylic and CNC routed starboard (a marine-grade polymer), were made to resemble a film strip. Next a coffee table was crafted out of an equipment road case filled with movie props. Studio logos were painted on the sides with the use of laser cut stencils, and with a glass top, gives the illusion it came off the set of a hollywood movie. The addition of a rebuilt movie poster marquee, movie posters, candy stand, pop corn machine, and with the existing soda fountain and the arcade in the loft, the home theater was almost complete.

In a fitting tribute, [Ed] designed and built a marquee sign to dedicate and name the theater after his cousin Greg, one of his closest friends and avid movie watcher, who had sadly passed away. Video overview of all the hard work after the break.

Looking at the receiver itself the white plastic dome of the PIR sensor should raise an eyebrow. Since the cable box takes a while to turn on [Ivan] included the motion sensor to switch that component on when you walk into the room. This way it’ll be ready to go by the time you sit down. It does this by sending IR signals from the PIC32 dev board. Of course the board has its own receiver to listen for the remote control commands. The remote buttons have been mapped a bit differently than originally intended. You can see in the diagram above that the normal VCR/DVD/DVR buttons have been set to control the room’s LED strips. There’s even a power consumption monitor rolled into the project. All of these features are demonstrated in the clip after the break.

This is a nearly perfect base setup. But we’d love to see it with a web interface at some point in the future.

Here’s an exercise in excess if we’ve ever seen one. While working on his undergrad at Michigan State, [Gregory] thought it would be a great idea to build an all-tube home theater system. He calls his seven-foot tall rack of amplifiers ‘Frankenstein,’ and we’ve got to agree this build is an impressive monstrosity of engineering prowess.

[Gregory]’s Frankenstein is a complete 5.1 home theater system. In the interests of sanity, the majority of the equipment in the rack is off-the-shelf gear including a CD player, surround sound processor, and a beautiful McIntosh solid state preamp. The power amps, though, are where this build really shines.

For the sub, [Gregory] built a wonderful monoblock tube amp, able to push nearly 300 watts into a subwoofer. The other channels for this home theater system are amplified with a huge four channel tube amp providing 480 watts per channel. In total, there are 23 tubes in [Gregory]’s amplifier system, enough to consume 20 amps of filament current.

You can check out [Gregory]’s demo video of his system after the break.

As you can see, there are a lot of wood parts that went into the cabinet. It starts with a base of 2×4 framing. From there the plywood sawdust really starts to fly as each component is produced. During assembly [Baccula] is careful to fully glue each joint — you don’t want to find out that your sub cabinet vibrates after you get everything installed. All together the new piece of living room furniture stands three feet tall and deep and two feet wide.

The album has no captions but you can read a bit more about the project in the Reddit comments.

Using IR repeaters for larger home theater setups is not uncommon, but they usually are quite simple. A series of IR receivers are placed throughout a home, all wired to repeat the signals in a central closet where all of the AV equipment is located. [Bill] constructed a solution that works much like a standard IR repeater setup, however his requires no receivers, and it can be used anywhere in the world, provided you have Internet access.

His project, called Ether IR, is an Internet-enabled IR repeater. It consists of an Ethernet-connected module with an IR LED mounted on it, capable of controlling your AV equipment. The board is hooked up to your LAN, and relays commands to your home theater via a simple web page. The equipment can then be controlled from any Internet-connected device, such as a mobile phone or tablet PC.

The entire project is open-source, so [Bill] has included schematics, instructions, and a bill of materials so that you can construct your own. The only issue at this point is the software portion of the project. The software is free, but the distribution method is in question – once things are sorted out, he will ensure that you can obtain the software for your Either-IR from him or directly from the Ethernet chip’s manufacturer.